I am new to this. I am an active 42 year old. I'm not sure what's wrong but for the last 2-3 years I've been suffering severe fatigue after rigotous exercise. It is usually accompanied by muscle tenderness, feverish feeling and general tiredness. The fatigue does not occur until 2-3+ hours after I finish exercising. I have been through several blood tests, stress tests and echocardigroam and nothing abnormal was detected. Not sure what to do and who to turn to?? Anyone else have a similar experience and can suggest a curse of action? I really need your help.